Cunningham studied civil engineering at UCLA before dropping out of school to play poker professionally. At the age of 18, he began playing at in Indian casinos. Previously a Full Tilt sponsored pro, he became a full member of Team Full Tilt in October 2006.

Cunningham earned the title 2005 ESPN/Toyota Player of the Year and came close to winning it again in 2006. He was also voted by fellow professional poker players the Best All Around Player under 35.

Cunningham's single largest tournament payout occurred at the 2006 World Series of Poker when he finished in fourth place in the Main Event, earning $3,628,513. Frequently during the tournament, when other players tried to take on Cunningham, ESPN's Norman Chad would respond with comments such as: "What are they thinking of? This is Allen Cunningham!"

Cunningham won the $300,000 'Mega Match' on Poker After Dark that aired the week of October 8, 2007. On December 7, 2007, Cunningham won the 15,000 buy-in inaugural National Poker League Vegas Open Championship Main Event after defeating David Singer during heads-up play, winning over $325,000.[1]

As of 2014, his total live tournament winnings exceed $11,500,000,[3] 17th on the all time winnings list.[4] As of August 2014, his 55 cashes including his five bracelets have netted him $7,097,407 in WSOP earnings.[5]